Make the Tapenade. Rinse the olives in running water to wash off the bottle stink. Place all ingredients (except the olive oil) in the bowl of the food processor. Process to combine, stopping to scrape down the sides of the bowl, until the mixture becomes a smooth paste, approximately 1 to 2 minutes total. Add the olive oil if necessary. Transfer to a bowl for plating.

Make the Sauce. Combine the Clamato, soy sauce and lime juice in a 3:2:1 ratio. Taste the resulting sauce and adjust the salt-acid balance to taste. Strain the resulting sauce through a very fine mesh strainer multiple times to get as clear and smooth a sauce as you reasonably can.

Slice the Fish. Using a sushi knife, long chef’s knife, long slicing knife or other long knife that is extremely sharp, slice perfect identically sized rectangles of each of the fish against the grain so that you have eight slices of each.

Plate the Crudo. Arrange two pieces of each fish on each plate in a checkerboard pattern so that each piece of the same fish is catty-corner to the other and the overall shape on the plate is rectilinear. Spoon some of the sauce over the top of the fish so that it just fans out around the fish. Top each piece of the grouper with a cilantro leaf. Top each piece of tuna with a bit (less than a quarter teaspoon) of the tapenade. Garnish the plate with a few drops of cilantro oil (if using).